Science is a cute, cuddly bunny: pet it

GM fish coming to your plate? So?

If I read another article about Frankenfish or Frankensalmon I might just design a Trojan to bring down any website/ computer / mobile / tablet that hosts them. These articles bring to mind images of double-headed Salmon and seven-finned abominations. Why all the fuss? The FDA (Food and Drug Administration, USA) are close to agreeing to the production of genetically modified (GM) salmon made by AquaBounty on a land-based Fort Knox in Panama, and sold – unlabelled – to the US market.

The villain of this story is an Atlantic salmon (Salmo salar) that has a single-copy of a growth hormone gene from the Chinook Salmon (Oncorhynchus tshawytscha) inserted into its genome. This growth hormone is under the control of an antifreeze gene promoter from the eel-like ocean pout (Zoarces americanus). The promoter keeps growth hormone production switched-on all year round instead of only in the warmer months. So this salmon can go from an egg to your plate in just 18 months instead of the normal 3-year process. Simply more fish in less time; economically it’s pretty brilliant.

The consumer should get more fish at a lower cost, however consumer groups are roaring “[they] jammed up the White House telephone lines last week protesting any approval” said Eve Mitchell, European food policy adviser at Food and Water Watch Europe. The two main concerns about GM fish are its effects on human health and the environment.

I’ve read over 20 articles about these fish and most journalists seem to assume that GM fish are bad for you, and implied that these fish might be highly allergic since the human body has never been exposed to this salmon before. My opinion: wishy-washy bull****, no data backs these claims, most proponents link allergenicity with seafood being highly allergic. The only decent article that discussed health was Henry Miller’s ‘Turning gene science into a fishy business’ in The Observer. His conclusion? Till now GM food has not resulted in huge health epidemics, although some cases of earlier imprecise genetic techniques, such as traditional crossbreeding, have resulted in new vegetable varieties with elevated toxin levels or disease weaknesses.

The FDA have given this GM salmon a clean bill of health, and the FDA has made the data publically available to appease critics. On the other hand, AquaBounty claims a lot without backing it up with publically available data (that I could easily find): Ron Stotish, the chief executive of AquaBounty “This is perhaps the most studied fish in history … Environmentally this is a very sustainable technology.” So my concerns started rising here.

The greatest fear is that these salmon could escape and cause the collapse of wild Atlantic salmon stock. This fear is based on the ‘Trojan Gene’ hypothesis initially coined by Howard and Muir in their seminal PNAS study in 1999. They inserted a salmon growth hormone gene into the Japanese medaga (Oryzias latipes) that makes the fish grow bigger and stronger. Predictably this resulted in dominance over wild type males and more less fit young being produced from GM males. The data was plugged into a computer model and extended over multiple generations. The result was extinction in nearly 50 generations if the GM males have a 4-fold mating advantage over wild type fish.

If applied to AquaBounty’s GM salmon an escape could lead to quick extinction of wild type Atlantic salmon. AquaBounty have already predicted this scenario and their facility is land-based. Unless these fish start evolving very quickly there is little chance they will escape. AquaBounty also subject their eggs to high pressures that results in eggs with 3 sets of chromosomes and 98% of adult salmon are rendered sterile.

The problem is that for AquaBounty to become profitable they need to sell their eggs to be raised on other farms in a number of countries. The U.K. has already banned GM fish from being grown in sea- or river-based pens, but will other countries have the appropriate legislation? Escapes are not uncommon. In the U.K. 100,000 farmed Atlantic salmon escaped in March. If these were Aquabounty’s GM salmon potentially over 2,000 fertile adults could of escaped into the wild, a catastrophe.

AquaBounty says that even if they do escape their GM salmon are more susceptible to the environment. They also say that male salmon do not gain mating advantages due to size. A study by Thomas et al. (1997, Proc. R. Soc. Lond. B) proves them wrong. Such blatant misinformation coupled with the companies desire not to release all of its data simply breeds mistrust.

AquaBounty are also trying to sell the idea that these fish are environmentally sustainable since they remove pressure on wild fish stocks. Theoretically this makes sense, replace our need and love of that pink flesh from wild salmon to GM salmon. The GM salmon will be cheaper, people will buy more, and so less wild salmon will be caught. Wrong. Since the 1990’s fish have become harder and more expensive to catch. Fish stocks have been dwindling worldwide. On the other hand, governments have been subsiding fisherman to keep them afloat and consumers are willing to pay more for their wild fish.

GM salmon are also unlikely to relieve wild fishing pressures any time soon, since farmed salmon are fed on fishmeal and fish oils that are made from wild stocks of makerel, sardines and smaller fish. Until this changes the proposed environmental benefits are very opaque.

These companies are only shooting themselves in the foot. People just won’t believe the data from AquaBounty, but no other third party research has been allowed on these salmon. Greater openness and collaboration with academics is sorely needed for the environmental (perhaps even health) issues to be addressed. Otherwise we will all be doomed to read about yet more Frankenfoods and the PR catastrophe that was GM crops will be repeated. If GM foods are truly harmless then they should be labelled and the public informed.

There are currently a dozen GM fish in the pipeline, 2 produced in China and Cuba. There is also a cow that has been modified for resistance to mad-cow disease and a so-called Enviropig. As its name suggests this pig is beneficial to the environment since it produces less phosphorous in its faeces. But unless we have more information and good scientific research performed on these animals I doubt anybody is going to be convinced about wanting to eat Enviropig bacon, no matter how good, cheap or beneficial they are. The anti-GM scare journalists are too great.